Outlook - Room Finder is no longer displaying meeting rooms

A known issue is when Outlook - Room Finder is no longer displaying meeting rooms more specifically in Outlook desktop application. Screenshot of the issue is mentioned as reference. Following solutions are proposed by Microsoft Support in case# 29354859‎ with internal ticket ID# 18693.

Solution1:
Create a room list by running the PowerShell through below steps:

1. Start - Windows PowerShell ISE - Run as Administrator
2. Install-Module -name ExchangeOnlineManagement
3. Import-Module -name ExchangeOnlineManagement
4. Connect-Exchangeonline
5. Run the following command to create a room list:
6. New-DistributionGroup <RoomListName> -RoomList -Members $Members
7. Run the following command to add existing rooms to the room list:
8. Add-DistributionGroupMember <RoomListName> -Member <RoomMailbox>

More Information: Room Finder doesn't display any conference rooms when a user creates a meeting - Exchange | Microsoft Docs

If the above solution does not work then try to update the registry settings as below
Solution2:

1. From the Start menu, type regedit.exe in the search box, and then press Enter.
2. If you are prompted for an administrator password or for confirmation, type the password or provide confirmation.
3. In Registry Editor, navigate to: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Options\Calendar
4. Right click on Calendar and select New DWord (32-bit) value.
5. Set the Name to ShowLegacyRoomFinder and press Enter.
6. Right click the new key, select Modify and set the Value data to 1.
7. Close Registry Editor and restart Outlook.

More Information: https://urldefense.com/v3/__https://support.microsoft.com/en-us/office/how-to-revert-the-outlook-desktop-webview-based-room-finder-to-the-legacy-room-finder-e872b6f2-0d36-41ff-861d-adaab2da9c28?ui=en-US&rs=en-US&ad=US__;!!PryGUe7zedMk!Fm5FkgcGC3rC2fENttWaeU9J4rSFtDbzxTV3uqVCanG6jN_JGnKr75BlqN7iMBL0GY7vgh4$